The invention relates to a cardiovascular and thoracic retractor, and in particular, to a retractor used for open heart surgery. It aids the heart surgeon by letting the surgeon have more control over the surgical procedures; by presenting a retractor having a wide range of adjustability to suit the individual morphology of patients; and by helping to eliminate precious time in the use of the device.
The heart is a hollow muscular pump which lies in the chest cavity in a loose protective sack called the pericardium. The mass of the heart is an extremely powerful thick layer of muscle called the mycocardium.
The heart is divided internally to form four chambers. The upper and lower chambers are separated on the right side by the tricuspid valve and on the left side by the mitral valve. Additional valves are located at the outlets from the vessels which leave the heart.
When any of these valves become diseased and fail to operate properly, it may become necessary to perform open heart surgery for correction of the problem. It is possible, for example, to surgically implant artificial heart valves or homograft replacements to replace the natural valves.
During heart surgery, the chest is opened, commonly by an incision several inches long along the axis of the sternum. A sternum retractor is used to maintain exposure of the heart. This retractor includes grips which fit on either side of the chest incision and are used first to open the incision and then to maintain retraction of the ribs and muscles of the chest.
Open heart surgery includes the further step of opening the thick muscular layers of the heart to expose the diseased inner portion of the heart, for example the mitral valve. Commonly a surgical assistant retracts the myocardium or the vessels surrounding the heart using retractor blades. Since the heart is an extremely powerful muscle, the present retraction technique presents the disadvantage that it requires strength and concentration on the part of the surgical assistant to maintain the constant tension necessary to expose the diseased valve. Further disadvantages of this technique are that the heart surgeon relinquishes control to the surgical assistant over this aspect of the operation and that this technique requires an additional person to be involved in the operation.
A device is known from the prior art which mechanically performs the job of the surgical assistant. This device utilizes retractor blades mounted on one grip of the sternal retractor to hold the myocardium open. The retractor blades are mounted at a stationary position relative to the sternal retractor grip. The blades include holes along the handle which lock on hooks on the grip. While several holes are provided along the blade handle and hooks are provided at various distances along the grip to give some flexibility in positioning the blades, the amount of adjustment presented by the known device is limited. In fact, the adjustment is so limited that many surgeons might be deterred from use of the device.
An advantage of the present invention is the wide range of continuous adjustablilty, not only for the distances which the blades extend from the retractor grip and the placement along the grip, but also for the angle, tilt, and rotation for the retractor blades. This feature is important to allow for the many morphological variations in individuals. Many of these differences cannot be anticipated until the surgeon has opened the chest or heart. The surgeon may even decide to vary the position of the retractors during surgery.
A further advantage of the present invention is that while it allows a great deal of adjustability, it is designed to allow the user to go from full adjustability to a locked position very easily.
Another advantage of the present invention is that it is designed for quick and easy assembly and disassembly.
The adjustability and the ease of use of this retractor add to the ultimate goal of any surgeon, and in particular of a heart surgeon; the device helps to simplify a complex operation by eliminating the need for a surgical assistant and allowing the heart surgeon more control and flexibility in performing the operation. Further the device is designed to allow infinite adjustability while decreasing time needed to prepare for open heart surgery and to finish the operation.